package com.bnz.servlet;

import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSON;
import com.bnz.pojo.Classes;
import com.bnz.service.ClassesService;
import com.bnz.service.impl.ClassesServiceImpl;

import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;

@WebServlet("/classes")
public class ClassesServlet extends HttpServlet {
    private ClassesService classesService;
    @Override
    public void init(){
        classesService = new ClassesServiceImpl();
    }
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        //1. 设置响应结果
        resp.setContentType("text/html;charset=utf8");
        //2. 得到cmd参数
        String cmd = req.getParameter("cmd");
        //3. 根据参数名调用不同的方法
        if(StrUtil.isNotBlank(cmd)){
            if("list".equals(cmd)){
                list(req,resp);
            }
        }
    }

    //班级列表
    private void list(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        //2.1 得到所有班级列表
        List<Classes> classesList = classesService.findAll();
        //2.2 转换为字符串并输出
        resp.getWriter().println(JSON.toJSONString(classesList));
        //2.3 刷新页面
        resp.getWriter().flush();
    }
}
